view rogue4/daemon.c @ 83:09db0cf536af

Properly handle invalid room references in savefiles. In all games, rs_write_room_reference() stored -1 for a nonexistent room, but rs_read_room_reference() did not check for out-of-bounds values, leading to pointers to rooms[-1], which sometimes caused crashes. rs_read_room_reference() has now been modified to use NULL instead. Some of the games required further changes to replace NULL with the pointer to the actual room. Others are capable of handling NULL for objects not in any room.
author John "Elwin" Edwards
date Thu, 08 Aug 2013 12:41:35 -0700
parents 9535a08ddc39
children f2951c4e28d9
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/*
 * Contains functions for dealing with things that happen in the
 * future.
 *
 * @(#)daemon.c	4.4 (Berkeley) 1/12/82
 *
 * Rogue: Exploring the Dungeons of Doom
 * Copyright (C) 1980, 1981, 1982 Michael Toy, Ken Arnold and Glenn Wichman
 * All rights reserved.
 *
 * See the file LICENSE.TXT for full copyright and licensing information.
 */

#include <curses.h>
#include "rogue.h"

#define EMPTY 0
#define DAEMON -1

#define _X_ { EMPTY }

struct delayed_action d_list[MAXDAEMONS] = {
    _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_,
    _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_, _X_, 
};

/*
 * d_slot:
 *	Find an empty slot in the daemon/fuse list
 */
struct delayed_action *
d_slot()
{
    register int i;
    register struct delayed_action *dev;

    for (i = 0, dev = d_list; i < MAXDAEMONS; i++, dev++)
	if (dev->d_type == EMPTY)
	    return dev;
#ifdef WIZARD
    debug("Ran out of fuse slots");
#endif
    return NULL;
}

/*
 * find_slot:
 *	Find a particular slot in the table
 */
struct delayed_action *
find_slot(func)
register int (*func)();
{
    register int i;
    register struct delayed_action *dev;

    for (i = 0, dev = d_list; i < MAXDAEMONS; i++, dev++)
	if (dev->d_type != EMPTY && func == dev->d_func)
	    return dev;
    return NULL;
}

/*
 * daemon:
 *	Start a daemon, takes a function.
 */
daemon(func, arg, type)
int (*func)(), arg, type;
{
    register struct delayed_action *dev;

    dev = d_slot();
    dev->d_type = type;
    dev->d_func = func;
    dev->d_arg = arg;
    dev->d_time = DAEMON;
}

/*
 * kill_daemon:
 *	Remove a daemon from the list
 */
kill_daemon(func)
int (*func)();
{
    register struct delayed_action *dev;

    if ((dev = find_slot(func)) == NULL)
	return;
    /*
     * Take it out of the list
     */
    dev->d_type = EMPTY;
}

/*
 * do_daemons:
 *	Run all the daemons that are active with the current flag,
 *	passing the argument to the function.
 */
do_daemons(flag)
register int flag;
{
    register struct delayed_action *dev;

    /*
     * Loop through the devil list
     */
    for (dev = d_list; dev <= &d_list[MAXDAEMONS-1]; dev++)
	/*
	 * Executing each one, giving it the proper arguments
	 */
	if (dev->d_type == flag && dev->d_time == DAEMON)
	    (*dev->d_func)(dev->d_arg);
}

/*
 * fuse:
 *	Start a fuse to go off in a certain number of turns
 */
fuse(func, arg, time, type)
int (*func)(), arg, time, type;
{
    register struct delayed_action *wire;

    wire = d_slot();
    wire->d_type = type;
    wire->d_func = func;
    wire->d_arg = arg;
    wire->d_time = time;
}

/*
 * lengthen:
 *	Increase the time until a fuse goes off
 */
lengthen(func, xtime)
int (*func)();
int xtime;
{
    register struct delayed_action *wire;

    if ((wire = find_slot(func)) == NULL)
	return;
    wire->d_time += xtime;
}

/*
 * extinguish:
 *	Put out a fuse
 */
extinguish(func)
int (*func)();
{
    register struct delayed_action *wire;

    if ((wire = find_slot(func)) == NULL)
	return;
    wire->d_type = EMPTY;
}

/*
 * do_fuses:
 *	Decrement counters and start needed fuses
 */
do_fuses(flag)
register int flag;
{
    register struct delayed_action *wire;

    /*
     * Step though the list
     */
    for (wire = d_list; wire <= &d_list[MAXDAEMONS-1]; wire++)
    {
	/*
	 * Decrementing counters and starting things we want.  We also need
	 * to remove the fuse from the list once it has gone off.
	 */
	if (flag == wire->d_type && wire->d_time > 0 && --wire->d_time == 0)
	{
	    wire->d_type = EMPTY;
	    (*wire->d_func)(wire->d_arg);
	}
     }
}